Systems and processes herein improve the conversion of propylene to ethylene via metathesis. On a mass basis, embodiments herein may be used to convert greater than 40% propylene, on a mass basis, to ethylene, such as 43% to 75%, on a mass basis. In one aspect, processes for the conversion of propylene to ethylene herein may include introducing a propylene feed stream to a metathesis reactor, and contacting the propylene with a metathesis catalyst in the metathesis reactor to convert the propylene to ethylene and 2-butene. An effluent from the metathesis reactor may be recovered, the effluent including ethylene, 2-butene, and unconverted propylene. The effluent may then be separated in a fractionation system to recover an ethylene fraction, a propylene fraction, a c4 fraction, and a C5+ fraction. The propylene fraction and the C4 fraction may then be fed to the metathesis reactor to produce additional ethylene.

Processes and systems for the conversion of propylene to ethylene may include introducing a propylene feed stream to a C3 metathesis reactor, converting the propylene to ethylene and 2-butene. The metathesis reactor effluent may be recovered and separated in a fractionation system to recover an ethylene product, a C3 fraction, a C4 fraction, and a C5+ fraction. All or a portion of the C3 fraction may be fed to the C3 metathesis reactor to produce additional ethylene. The C4 fraction may be converted in a C4 isomerization/metathesis reaction zone by: (i) isomerization of 2-butenes to 1-butene, (ii) metathesis of the 1-butene and 2-butene to produce propylene and 2-pentene, and/or (iii) autometathesis of the 1-butene to produce ethylene and 3-hexene. An effluent from the C4 isomerization/metathesis reaction zone may then be recovered and fed from the C4 isomerization/metathesis reaction zone to the fractionation system.

Processes and systems for the conversion of propylene to ethylene may include introducing a propylene feed stream to a C3 metathesis reactor, converting the propylene to ethylene and 2-butene. The metathesis reactor effluent may be recovered and separated in a fractionation system to recover an ethylene product, a C3 fraction, a C4 fraction, and a C5+ fraction. All or a portion of the C3 fraction may be fed to the C3 metathesis reactor to produce additional ethylene. The C4 fraction may be converted in a C4 isomerization/metathesis reaction zone by: (i) isomerization of 2-butenes to 1-butene, (ii) metathesis of the 1-butene and 2-butene to produce propylene and 2-pentene, and/or (iii) autometathesis of the 1-butene to produce ethylene and 3-hexene. An effluent from the C4 isomerization/metathesis reaction zone may then be recovered and fed from the C4 isomerization/metathesis reaction zone to the fractionation system.

The present disclosure provides oxidative coupling of methane (OCM) systems for small scale and world scale production of olefins. An OCM system may comprise an OCM subsystem that generates a product stream comprising C.sub.2+ compounds and non-C.sub.2+ impurities from methane and an oxidizing agent. At least one separations subsystem downstream of, and fluidically coupled to, the OCM subsystem can be used to separate the non-C.sub.2+ impurities from the C.sub.2+ compounds. A methanation subsystem downstream and fluidically coupled to the OCM subsystem can be used to react H.sub.2 with CO and/or CO.sub.2 in the non-C.sub.2+ impurities to generate methane, which can be recycled to the OCM subsystem. The OCM system can be integrated in a non-OCM system, such as a natural gas liquids system or an existing ethylene cracker.

The present disclosure provides oxidative coupling of methane (OCM) systems for small scale and world scale production of olefins. An OCM system may comprise an OCM subsystem that generates a product stream comprising C.sub.2+ compounds and non-C.sub.2+ impurities from methane and an oxidizing agent. At least one separations subsystem downstream of, and fluidically coupled to, the OCM subsystem can be used to separate the non-C.sub.2+ impurities from the C.sub.2+ compounds. A methanation subsystem downstream and fluidically coupled to the OCM subsystem can be used to react H.sub.2 with CO and/or CO.sub.2 in the non-C.sub.2+ impurities to generate methane, which can be recycled to the OCM subsystem. The OCM system can be integrated in a non-OCM system, such as a natural gas liquids system or an existing ethylene cracker.

The present disclosure relates to processes that catalytically convert a hydrocarbon feed stream predominantly comprising both isopentane and n-pentane to yield upgraded hydrocarbon products that are suitable for use either as a blend component of liquid transportation fuels or as an intermediate in the production of other value-added chemicals. The hydrocarbon feed stream is isomerized in a first reaction zone to convert at least a portion of the n-pentane to isopentane, followed by catalytic-activation of the isomerization effluent in a second reaction zone with an activation catalyst to produce an activation effluent. The process increases the conversion of the hydrocarbon feed stream to olefins and aromatics, while minimizing the production of C1-C4 light paraffins. Certain embodiments provide for further upgrading of at least a portion of the activation effluent by either oligomerization or alkylation.

The present disclosure relates to processes that catalytically convert a hydrocarbon feed stream predominantly comprising both isopentane and n-pentane to yield upgraded hydrocarbon products that are suitable for use either as a blend component of liquid transportation fuels or as an intermediate in the production of other value-added chemicals. The hydrocarbon feed stream is isomerized in a first reaction zone to convert at least a portion of the n-pentane to isopentane, followed by catalytic-activation of the isomerization effluent in a second reaction zone with an activation catalyst to produce an activation effluent. The process increases the conversion of the hydrocarbon feed stream to olefins and aromatics, while minimizing the production of C1-C4 light paraffins. Certain embodiments provide for further upgrading of at least a portion of the activation effluent by either oligomerization or alkylation.

A distillation probe includes a conduit having a central axis. In addition, the distillation probe includes a baffle assembly disposed in the conduit. The baffle assembly includes a plurality of axially-spaced baffles positioned one-above-the-other in a stack within the conduit. Further, the distillation probe includes a first helical cooling coil wrapped around the conduit. Moreover, the distillation probe includes a thermally conductive layer disposed about the conduit and encapsulating the first helical cooling coil. The thermally conductive layer is configured to transfer thermal energy between the first helical cooling coil and the conduit.

A distillation probe includes a conduit having a central axis. In addition, the distillation probe includes a baffle assembly disposed in the conduit. The baffle assembly includes a plurality of axially-spaced baffles positioned one-above-the-other in a stack within the conduit. Further, the distillation probe includes a first helical cooling coil wrapped around the conduit. Moreover, the distillation probe includes a thermally conductive layer disposed about the conduit and encapsulating the first helical cooling coil. The thermally conductive layer is configured to transfer thermal energy between the first helical cooling coil and the conduit.

A distillation probe includes a conduit having a central axis. In addition, the distillation probe includes a baffle assembly disposed in the conduit. The baffle assembly includes a plurality of axially-spaced baffles positioned one-above-the-other in a stack within the conduit. Further, the distillation probe includes a first helical cooling coil wrapped around the conduit. Moreover, the distillation probe includes a thermally conductive layer disposed about the conduit and encapsulating the first helical cooling coil. The thermally conductive layer is configured to transfer thermal energy between the first helical cooling coil and the conduit.